The present invention relates to a curtain airbag device. The present invention also relates to a curtain airbag that, for example, inflates along a window on a side-door of a vehicle when the vehicle is involved in a side-on collision or rollover.
In a typical curtain airbag device the curtain airbag is disposed adjacent to an inner edge part of a vehicle cabin where the ceiling and a side surface meet. When gas is introduced into the curtain airbag through a gas-entrance hole, the curtain airbag inflates along, for example, a window on a side-door.
In addition to reducing impact by restraining, for example, the head of a vehicle occupant, this curtain airbag is capable of keeping a vehicle occupant inside the vehicle cabin (i.e. the airbag functions to hold a vehicle occupant inside a vehicle cabin).
Japanese Unexamined Patent Application Publication No. 2002-220023 (incorporated by reference herein) discloses a curtain airbag device having a curtain airbag whose rear portion is provided with a triangular non-inflatable fabric. A tip section of the triangular fabric is mounted on a roof-side rail.
According to this curtain airbag device, when the curtain airbag is to be inflated, a lower tip section of the triangular non-inflatable fabric is pulled downward. This creates high tension at the lower edge of the curtain airbag in the front-rear direction of the vehicle body. On the other hand, the tension at a region above the lower edge of the curtain airbag is relatively lower. This creates a state in which the curtain airbag has a hammock-like structure, and thus improves the function for holding a vehicle occupant inside a vehicle cabin.